All arithmetical and logical operations within a computer/server configuration are tackled by its Central Processing Unit, or CPU. This hardware element is oftentimes called the "brains" of the personal computer too. The rate at which the CPU completes system instructions is typically referred to as its speed and it is measured in Hertz. The swifter the processing unit is, the speedier scripts and web programs will be executed, although the general performance of the latter is dependent upon other things also - the read/write speed of the hard disk, the amount of physical memory, the network connectivity, and so on. All newer CPUs have a number of cores, that work together. Because of this, the efficiency and the workload that a CPU can manage increase, since each and every core can process a number of tasks separately and a number of cores can handle 1 task which cannot be processed by a single core.